"   24 (2nd series).   No punishment ..............  Reward for each trial

"   25-30 ...........  Same as on 24th ............

July 1 (1st series).    No punishment ..............   "     "   "     "

" 1 (2nd series).  Return to starting point ...  Reward only for correct first
choices
" 2-8 .............  Same as on July 1 ..........

"   8 (2nd series).    No punishment ..............  Reward for each trial

" 8 (3rd series).  Return to starting point ...  Reward only for correct first
choices

"   9-10 ............  Same as for July 8 (3rd series)

"   10 (2nd series).   Momentary confinement in .....  Reward for each correct choice
wrong boxes

"   12 ..............  Return to starting point .....  Reward for correct first choice

"   12 (2nd series).  30 sec. confinement ..........  Reward for each correct choice

"   12 (3rd series).  5   "        " ...............    "    "   "      "      "

"   13 .............. 30  "        " ...............    "    "   "      "      "

"   14-17 ...........  Return to starting point .....  Reward for correct first choices

"   17 (2nd series).  60 sec. confinement ..........  Reward for each correct choice

"   19 .............. 30  "        " ...............    "    "   "      "      "

"   20-26 ........... 10  "        " ...............    "    "   "      "      "

"   27-30 ...........  Right box indicated by slight  Reward in each right box
raising of exit door
momentarily. 
No punishment

"   30 (2nd series).   Return to starting point .....  Reward for correct first choices

"   31 ..............    "   "     "       "   .....    "    "     "      "      "

 " 31 (2nd series)
       to Aug. 10 .... 10 to 60 sec. confinement ....  Reward for each correct choice

Aug. 10 (2nd series).   Threatened with whip .........    "    "   "      "       "

"   11 (1st series).      "        "   " ...........    "    "   "      "       "

"   11 (2nd series).  10 sec. confinement ..........    "    "   "      "       "

"   12 ..............  Threatened with whip .........    "    "   "      "       "

"   12 (2nd series).  10 sec. confinement ..........    "    "   "      "       "

"   19 .............. 10  "        " ...............    "    "   "      "       "

"   19 (2nd series).   Threatened with whip .........    "    "   "      "       "

With the above reactive tendencies and modifications of method in mind we may continue our description of results.  On June 9 there developed a tendency to increase the magnitude of the original error by choosing nearer the left end of the groups.  This is odd, since one would naturally suppose that an animal as intelligent as the orang utan would tend